1. Filed of the Invention
The present invention relates to an ink-jet head provided in a printer or the like and a method of manufacturing the same.
2. Description of the Related Art
An ink-jet head used for a printer, a facsimile or the like includes a front end as a flow path unit in which thin plates are laminated and an ink flow path is formed. A nozzle plate in which plural nozzles for discharging ink are arranged is bonded to one surface of the front end. A reservoir is provided on the other surface of the front end, and supports and reinforces the thin front end.
JP-A-8-174825 (pages 2 to 4, FIG. 7) discloses a method of bonding a front end and a nozzle plate. Through holes are formed in plural thin plates constituting the front end and the nozzle plate. A positioning pin is fitted in the through holes, and the respective layers are laminated through adhesive, so that the front end and the nozzle plate are positioned and are bonded. By this, a nozzle is disposed at a specified position with respect to an ink flow path.
The position accuracy of the nozzle with respect to the ink flow path has a great influence on a discharge characteristic, and in order to ensure high discharge accuracy, it is necessary to position the front end and the nozzle plate with high accuracy. Thus, a method is conceivable in which after the respective layers of the front end are previously bonded to each other, the front end and the nozzle plate are positioned and are bonded.
FIGS. 13 and 14 are sectional views showing a manufacture process of an ink-jet head. A first and a second positioning holes 76b and 76c and through holes 76a and 76d are formed in a front end 76. The through hole 76d is provided coaxially with the second positioning hole 76c, and its diameter is larger than that of the second positioning hole 76c. 
A nozzle positioning hole 29a and a through hole 29b are formed in a nozzle plate 29. The diameter of the through hole 29b is larger than that of the second positioning hole 76c. In the front end 76, a positioning pin (not shown) is fitted in the through hole 76a so that respective thin plates are positioned, and the respective layers are previously bonded to each other.
A positioning pin 91 is fitted in the first positioning hole 76b and the nozzle positioning hole 29a, and the front end 76 and the nozzle plate 29 are positioned and are bonded to each other. By this, a flow path unit 2 is formed and a nozzle (not shown) is positioned with high accuracy with respect to an ink flow path (not shown).
Next, as shown in FIG. 14, a reservoir 75 is formed by laminating thick plates, and a through hole 75a and a reservoir positioning hole 75b are formed. In the reservoir 75, a positioning pin (not shown) is fitted in the through hole 75a so that the respective thick plates are positioned and the respective layers are previously bonded to each other.
A positioning pin 92 is fitted in the second positioning hole 76c and the reservoir positioning hole 75b through the through holes 29b and 76d, and the front end 76 and the reservoir 75 are positioned and are bonded. By this, the nozzle plate 29, the front end 76 and the reservoir 75 are formed as one body.